Charlotte Uhlenbroek is on the north-west coast of Madagascar looking at lemurs called black lemurs even though the females are brown. The females have the upper hand and do not mind showing it if the males are a nuisance. A male tries to woo a female with his anal gland, but she is distinctly unimpressed. Black lemurs are good at finding different kinds of food, but while doing it they also play a key role in keeping their forests alive. They have a sweet tooth and love the nectar of the traveller’s palm. They gather enthusiastically, their noses buried deep in the palm. In return for a drink of nectar, the lemurs act like bees and carry the precious pollen to fertilise the next palm. A male bites into a millipede and smears its chemical secretions all over his body. It smells like disinfectant and some people have suggested that it acts rather like an insect repellent. But maybe there is more to it than that as he just can not seem to get enough.